ABB PVI Series grid-tie inverters feature high energy yield and performance efficiencies of up to 97%. These inverters have a field-adjustable “start-up voltage” point that allows low-end PV operating voltage down to 90 VDC. While there is some loss of efficiency at lower voltage settings, inverters can operate with as few as five standard 60-cell modules in series. Please see the inverter sizing chart in the System Design section for configurations that work in most areas. All ABB inverters come with a 10-year warranty.

ABB PVI and UNO Transformerless Inverters

The ABB PVI and UNOseries of inverters are some of the most flexible string inverters available. These ABB inverters have two separate MPPT inputs, allowing for two sub-arrays to be configured with differing string lengths, orientations, or even different PV modules. Conditions on one MPPT will not affect the other. Additionally, the 5 kW and larger inverters have two input terminals for each separate MPPT section allowing as many as four strings of modules (two on each MPPT) to be connected without separate string fusing. Both MPPT inputs can also be paralleled for use with a single array. A wide input voltage range allows for smaller installations with reduced string sizes where needed.

Where NEC 2014 690.12 rapid shutdown code requirements have been adopted, ABB has introduced two new versions of the ABB Rapid Shutdown Boxwhich cuts off DC voltage and current between the array and the inverter when activated. ABB transformerless single-phase inverters are available in sizes covering most common residential requirements, and can be used in groups of three for commercial three-phase applications. The transformerless design reduces internal power losses for high efficiencies. Output voltage can be set to 240 VAC split-phase, or 208 VAC or 277 VAC (480 VAC WYE) for three-phase systems.